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It takes two lines but is easier to use and read than the alternative:
(Get-wmiobject win32_operatingsystem).OSarchitecture
The latter would require entering the entire line to access the property. If you only need the one property then
$Bitness = (Get-wmiobject win32_operatingsystem).OSarchitecture
is better to use as it stores the string found in "OSarchitecture" instead of storing the whole object.
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